Ask PYS: Navigation

Cory, on Sep 14, 2011 asked:

I have a Raymarine chartplotter with a NMEA 0183 GPS. I would like to add an AIS receiver and weather station, which are both also NMEA 0183, but my chartplotter does not have enough NMEA 0183 ports. How can I make this work?

Hi Cory,

Your situation highlights one drawback of NMEA 0183 as opposed to NMEA 2000, which can support dozens of devices on a single port. There is a device that will help work around this problem. It is a NMEA 0183 multiplexer. A multiplexer can essentially channel the data from multiple ports into one output stream. In your case, allow your three devices to share one input port of your chartplotter.
But be aware that the NMEA 0183 multiplexer does have its own limitations and should be used with care.